Andy Pettitte outpitched Oakland All-Star Justin Duchscherer, getting just enough run support from Jason Giambi’s homer and a sacrifice fly by Alex Rodriguez to help the Yankees hold off the Athletics 2-1 yesterday for a three-game sweep.

The Yankees (53-45) won their seventh straight at home and climbed a season-best eight games over .500, entering a three-game series against Minnesota beginning tonight. Their winning streak at Yankee Stadium is their longest since last September.

The Athletics have dropped five straight, managing just nine runs in the process.

Perhaps accustomed to steamy afternoons in his native Texas, Pettitte (11-7) was sharp from the start. He gave up only four hits in eight innings, matching his longest outing of the year, and struck out nine without a walk.

Pettitte only faced more than three batters in the third and sixth before turning it over to Mariano Rivera, who worked a wild ninth for his 24th save in 24 chances.

Ryan Sweeney singled with one out and Bobby Crosby followed with a high fly to right that gave Bobby Abreu trouble as he looked up into the sun. Abreu made the grab — momentarily — and then dropped the ball.

First base umpire Hunter Wendelstedt ruled that Abreu never caught the ball, and the right fielder immediately tried to get Sweeney — who had retreated to first — at second base for the forceout.

His throw was high, though, and Rodriguez alertly cut it off near shortstop and tossed to Derek Jeter in time to get Sweeney.

Rajai Davis, pinch running for Crosby, tried to steal second moments later, and Jose Molina delivered a strong throw for the final out.

Duchscherer (10-6), who was so ill during last Tuesday’s All-Star game that he could barely pitch, lasted seven innings and gave up seven hits. The American League’s ERA leader still hasn’t allowed more than three earned runs in a game this season.